Capacitor sheet, electro-optical device with capacitor, flexible substrate, composite build-up substrate, and electronic apparatus

ABSTRACT

To stably mount an external capacitor in an electro-optical device. A film capacitor sheet  400  is attached to an electro-optical device so as to cover the entire reverse side of an element substrate  101  excluding a display region  101   a.  On the film capacitor sheet  400,  a plurality of film capacitors  410, 420, 430,  and  440  are formed in each region. As shown in FIG.  3 ( b ) or ( c ), each film capacitor is formed by alternately stacking a plurality of conductor plates  414  (or  434 ) and a plurality of dielectric films  416  (or  436 ) and by making lead wires ( 412  and the like) protrude. The dielectric films  416  are manufactured by mixing barium titanate powder with a flexible material and by forming the mixture into the shape of a film.

BACKGROUND OF THE INVENTION

[0001] 1. Field of Invention

[0002] The present invention relates to capacitor sheets suitable foruse in electro-optical devices and other various electronic apparatuses,electro-optical devices with capacitors, flexible substrates, compositebuild-up substrates, and electronic apparatuses.

[0003] 2. Description of Related Art

[0004] Electro-optical devices, such as liquid crystal panels usingliquid crystal as an electro-optical material, are widely used asdisplay devices in place of cathode-ray tubes (CRT) in displays ofvarious information processing apparatuses and liquid crystaltelevisions. For example, a conventional electro-optical device has thefollowing arrangement. Specifically, the conventional electro-opticaldevice includes an element substrate having pixel electrodes aligned inthe form of a matrix and switching elements such as TFTs (Thin FilmTransistors) connected to the pixel electrodes, an opposing substratehaving a counter electrode opposed to the pixel electrodes, and liquidcrystal, i.e., electro-optical material, filled between the twosubstrates.

[0005] With this arrangement, when a scanning signal is supplied to theswitching element via a scanning line, the switching element becomesconducting. In this conducting state, when an image signal with avoltage in accordance with a gray level is supplied to the pixelelectrode through a data line, a charge in accordance with the voltageof the image signal is accumulated in a liquid crystal layer between thepixel electrode and the counter electrode. When the switching element isturned off after the charge has been accumulated, the accumulated chargein the liquid crystal layer is maintained by the capacitance between thepixel electrode and the counter electrode and by a storage capacitance.Accordingly, when the switching elements are driven so as to control theamount of charge to be accumulated in accordance with the gray level,light is modulated according to each pixel, and the display gray levelvaries, thus performing gray-scale display.

[0006] It is only necessary to accumulate charge in an electrode of eachpixel for a partial period of a period for which one screen isdisplayed. First, a scanning-line drive circuit sequentially selectseach scanning line. Second, a data-line drive circuit sequentiallyselects each data line within the scanning-line selection period. Third,an image signal with a voltage in accordance with a gray level issampled on the selected data line. As a result, time-divisionmultiplexing driving in which the scanning line and the data line areshared by a plurality of pixels is made possible.

[0007] Liquid crystal panels have a structure formed by bondingtogether, with a predetermined gap therebetween, an element substratehaving pixel electrodes and an opposing substrate having a counterelectrode, the element substrate and the opposing substrate holdingtherebetween liquid crystal as an electro-optical material. The elementsubstrate and the opposing substrate are amorphous substrates formed ofglass or quartz. Recently, technology for mounting an integrated circuithaving a drive circuit on the element substrate by COG (chip on glass)or TAB (Tape Automated Bonding) and for integrally forming the liquidcrystal panel and the drive circuit has been developed. The integratedcircuit is formed by forming the drive circuit on a chip, which islargely formed of single-crystal silicon, and by sealing the chip withresin. On the element substrate, a pattern for inputting an image signalfrom an external device is formed. A flexible tape wire is connected tothe pattern.

SUMMARY OF THE INVENTION

[0008] The drive circuit of the liquid crystal panel requires acapacitor for smoothing a power supply voltage and for boosting voltageusing a charge pumping system. There has been a problem with the mannerin which the capacitor is mounted. For example, the capacitor can beformed in the interior of a semiconductor chip in the integratedcircuit. Since the capacitor occupies a relatively large area of theinterior of the integrated circuit, the semiconductor chip increases insize, and hence the semiconductor chip becomes expensive.

[0009] Concerning technology for externally attaching the capacitor, thecapacitor may be formed by a ceramic-type chip capacitor, and thecapacitor may be mounted on a flexible tape wire. The flexible tape wireis flexible, whereas the chip capacitor is rigid. Thus, metal fatigueoccurs in a joint portion between the flexible tape wire and the chipcapacitor. It thus becomes easier for the chip capacitor to fall off theflexible tape wire. Alternatively, the chip capacitor can be mounted onthe element substrate.

[0010] The chip capacitor is thicker than the integrated circuit, and itis difficult to mount the chip capacitor on the element substrate formedof glass or quartz. When the chip capacitor is forcedly mounted on theelement substrate, the chip capacitor easily falls off because ofvibrations and because of differences in the thermal spreadingcoefficient.

[0011] In view of the foregoing circumstances, it is a first object ofthe present invention to provide a capacitor sheet which is inexpensiveand which can be mounted stably, an electro-optical device with acapacitor, a flexible substrate, a composite build-up substrate, and anelectronic apparatus. It is a second object of the present invention toenhance a light-blocking effect in a non-display region of theelectro-optical device.

[0012] In order to solve the foregoing problems, the present inventionhas the following structure, wherein examples are placed withinparentheses.

[0013] A capacitor sheet (400) as set forth in claim 1 forms a capacitorhaving a single-layer structure or a multi-layer structure. Thecapacitor includes a dielectric layer (dielectric film 416) which is aflexible sheet formed by mixing dielectric material (barium titanate,etc.) powder with a polymeric material polyethylene, resist, etc.) andconductor layers (conductor plates 414) which are flexible and which areformed so as to hold the dielectric layer therebetween.

[0014] An electro-optical device with a capacitor as set forth in claim2 includes the electro-optical device including a plurality of scanninglines (112), a plurality of data lines (114), and pixels (pixelelectrodes 118) arranged in correspondence with intersections of thescanning lines and the data lines and a capacitor sheet (400) as setforth in claim 1, which is fixed to the electro-optical device.

[0015] In a structure as set forth in claim 3, according to theelectro-optical device with the capacitor as set forth in claim 2, theelectro-optical device includes a display region (101 a) for displayinginformation when being irradiated with external irradiation light. Thecapacitor sheet (400) is mounted along the periphery of the displayregion (101 a), whereby a portion in which the capacitor sheet (400) ismounted is shielded from the irradiation light.

[0016] In a structure as set forth in claim 4, according to theelectro-optical device with the capacitor as set forth in claim 2, thecapacitor sheet has shock resistance.

[0017] In a structure as set forth in claim 5, according to thecapacitor sheet as set forth in claim 1, the capacitor sheet is formedby a plurality of capacitors (410, 420, 430, and 440) formed in eachregion on a surface of the sheet.

[0018] A flexible substrate as set forth in claim 6 includes a capacitorsheet (400) as set forth in claim 1, the capacitor sheet (400) beingmounted on a top surface of the flexible substrate or being included asa layer in the flexible substrate.

[0019] A composite build-up substrate as set forth in claim 7 includes acapacitor sheet (400) as set forth in claim 1, the capacitor sheet (400)being mounted on a top surface of the composite build-up substrate orbeing included as a layer in the composite build-up substrate.

[0020] An electronic apparatus as set forth in claim 8 has a capacitorsheet as set forth in claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]FIG. 1 is a block diagram showing the electrical structure of anelectro-optical device according to an embodiment of the presentinvention.

[0022]FIG. 2 includes diagrams showing the structure of theelectro-optical device in this embodiment.

[0023]FIG. 3 includes illustrations showing details of a film capacitorsheet 400 in this embodiment.

[0024]FIG. 4 includes illustrations showing examples of variouselectronic apparatuses to which the electro-optical device is applied.

[0025]FIG. 5 includes illustrations showing modifications of the filmcapacitor sheet 400.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0026] 1. Structure of the Embodiments

[0027] 1.1 Overall Structure

[0028] With reference to FIG. 1, the structure of an electro-opticaldevice according to an embodiment of the present invention will now bedescribed.

[0029] In the drawing, a high-level device (not shown) supplies avertical synchronization signal Vs, a horizontal synchronization signalHs, and dot clock signals DCLK of input gray-scale data D0 to D2 to atiming-signal generating circuit 200. An oscillation circuit 150supplies a reading timing reference clock RCLK to the timing-signalgenerating circuit 200. In accordance with these signals, thetiming-signal generating circuit 200 generates various timing signalsand clock signals, which will be described below. A field reverse signalFR is a signal whose polarity is inverted every frame.

[0030] A drive signal LCOM is a signal supplied to a counter electrodeon an opposing substrate. In this embodiment, the drive signal LCOM isat a constant potential (zero potential). A start pulse DY is a pulsesignal output at the beginning of each frame. A clock signal CLY is asignal defining a horizontal scanning interval of a scanning side (Yside). A latch pulse LP is a pulse signal output at the beginning of thehorizontal scanning interval. The latch pulse LP is output when thelevel of the clock signal CLY changes (that is, rising edge and fallingedge). A clock signal CLX is a dot clock signal for display.

[0031] In a display region 101 a on an element substrate 101, aplurality of scanning lines 112 are formed extending in the X (row)direction. Also, a plurality of data lines 114 are formed extending inthe Y (column) direction. Pixels 110 are formed corresponding tointersections of the scanning lines 112 and the data lines 114, and thepixels 110 are aligned in the form of a matrix. In order to simplify thedescription, the total number of scanning lines 112 is m, and the totalnumber of data lines 114 is n (where m and n are integers of 2 or more),and the electro-optical device is described as an m ×n matrix displaydevice.

[0032] A scanning-line drive circuit 130 transfers the start pulse DYsupplied at the beginning of a frame in accordance with the clock signalCLY and sequentially and exclusively supplies the start pulse DY tofirst ends of the scanning lines 112 as scanning signals G1, G2, G3, . .. , Gm. A scanning-line drive circuit 160 is structured similarly to thescanning-line drive circuit 130. In accordance with the same timing asthe scanning-line drive circuit 130, the scanning-line drive circuit 160sequentially and exclusively supplies the scanning signals G1, G2, G3, .. . , Gm to second ends of the scanning lines 112. The scanning signalsare supplied from both the scanning-line drive circuits 130 and 160 inorder to suppress a voltage drop on the scanning lines 112 and tostabilize the operation.

[0033] A data converter circuit 300 converts the input gray-scale dataD0 to D2, which is input in synchronization with the dot clock signalDCLK, into a data signal Ds which is an analog signal in synchronizationwith the clock signal CLX and outputs the data signal Ds. The level ofthe data signal Ds is proportional to the gray-scale data D0 to D2. Thelevel of the data signal Ds is set so that the data signal Ds is atvoltage V1 in full-scale (when the gray-scale data DO to D2 is “111”).

[0034] A data-line drive circuit 140 sequentially samples and holds ndata signals Ds, n corresponding to the number of data lines 114 in ahorizontal scanning interval, and simultaneously supplies thesampled-held n data signals Ds in the subsequent horizontal scanninginterval through a buffer circuit to the corresponding data lines 114 asdata signals d1, d2, d3, . . . dn.

[0035] 1.2 Structure of Electro-optical Device

[0036] The structure of the above-described electro-optical device willnow be described with reference to FIGS. 2(a ) and (b). FIG. 2(a) is aplan view showing the structure of an electro-optical device 100. FIG.2(b) is a sectional view taken along the line A-A′ of FIG. 2(a). Asshown in these drawings, the electro-optical device 100 has a structureformed by bonding together, with a predetermined gap therebetween, theelement substrate 101 having pixel electrodes 118 and an opposingsubstrate 102 having a counter electrode 108 by a sealing member 104.The element substrate 101 and the opposing substrate 102 holdtherebetween liquid crystal 105 as an electro-optical material.

[0037] In fact, the sealing member 104 has a notch. After sealing in theliquid crystal 105 through the notch, the notch is sealed by sealant.However, the notch and the sealant are not shown in these drawings. Theelement substrate 101 and the opposing substrate 102 are amorphoussubstrates made of glass or quartz. The pixel electrodes 118 are formedby TFTs which are formed by depositing low-temperature polysilicon onthe element substrate 101. In other words, the electro-optical device100 is used as a transmissive type device.

[0038] At the back of the element substrate 101, a film capacitor sheet400 is provided in an outside region of the display region 101 a. In aregion outside the display region 101 a and inside the sealing member104, as in pixel transistors 116, the scanning-line drive circuits 130and 160 are formed by thin-film transistors on the substrate inrectangular regions 130 a and 160 a along a left-hand side 101 b and aright-hand side 101 c, respectively, as shown in the drawing. The filmcapacitor sheet 400 also functions as a light-blocking film for thescanning-line drive circuits 130 and 160 and prevents light fromentering the drive circuits formed in this region.

[0039] Compared with the other sides, a lower side 101 d of the elementsubstrate 101 is farther distant from the display region 101 a. Betweenthe sealing member 104 and the lower side 101 d, an integrated circuit170, which is an IC chip, is mounted by COP (chip on glass) or TAB (TapeAutomated Bonding). A substantially U-shaped terminal region 107 isformed in a protruding portion of the element substrate 101, theprotruding portion protruding above the opposing substrate 102.

[0040] A plurality of connection terminals are provided in the terminalregion 107. External control signals and power are input through aflexible tape cable 180. A connection terminal of the film capacitorsheet 400 is also connected to the terminal region 107. The structurewill be described later.

[0041] In contrast, the counter electrode 108 on the opposing substrate102 conducts electricity to a connection terminal on the elementsubstrate 101 by a conductive member (not shown) which is provided in atleast one corner of four corners at which the counter electrode 108 isbonded to the opposing substrate 102. Specifically, the drive signalLCOM is supplied to the opposing electrode 108 through the connectionterminal provided on the element substrate 101 and the conductivemember.

[0042] The integrated circuit 170 is formed by forming the data-linedrive circuit 140, the oscillation circuit 150, the timing-signalgenerating circuit 200, and the data converter circuit 300 on a chip,which is mainly formed of single-crystal silicon, and the chip is sealedwith resin. As described with reference to FIG. 1, the timing-signalgenerating circuit 200 supplies the start pulse DY and the clock signalCLY to the scanning-line drive circuits 130 and 160. These signals aretransferred through L-shaped patterns 171 and 172, which protrude to theleft and to the right from the integrated circuit 170 toward the regions130 a and 160 a, respectively. As in normal digital integrated circuits,the circuits in the integrated circuit 170 can be operated by a lowpower supply voltage of approximately 3 V. Thus, the power consumptionof the timing-signal generating circuit 200 and the data-line drivecircuit 140 can be suppressed.

[0043] In accordance with the usage of the electro-optical device 100,for example, when the electro-optical device 100 is adirect-viewing-type device, first, color filters which are aligned instripes or in the form of a mosaic or a triangle are provided on theopposing substrate 102. Second, for example, a light-blocking film(black matrix) made of metal material or resin is formed on the opposingsubstrate 102. For example, when the electro-optical device 100 is adirect-viewing-type device, a front light unit for irradiating theelectro-optical device 100 with light from the opposing substrate 102side or a backlight unit for irradiating the electro-optical device 100with light from the element substrate 101 side is provided if necessary.On electrode-forming surfaces of the element substrate 101 and theopposing substrate 102, alignment films (not shown) which are rubbed inpredetermined directions are formed, respectively, defining alignmentdirections of liquid crystal molecules in a no-voltage-applied state. Incontrast, at the opposing substrate 102 side, a polarizer (not shown) inaccordance with the alignment direction is formed. If polymer dispersedliquid crystal in which the liquid crystal is dispersed asmicroparticles in a polymer is used as the liquid crystal 105, theabove-described alignment films and the polarizer become unnecessary. Asa result, the efficiency in light utilization is increased. It istherefore advantageous in increasing luminance and reducing powerconsumption.

[0044] 1.3 Structure of Film Capacitor Sheet 400

[0045] With reference to FIGS. 3(a) to (c), the structure of the filmcapacitor sheet 400 will now be described. FIG. 3(a) is a back view ofthe electro-optical device 100, showing a state wherein the filmcapacitor sheet 400 is being mounted. In the drawing, the film capacitorsheet 400 has substantially the same dimensions as the element substrate101, except for a hollow portion corresponding to the display region 101a. In other words, the film capacitor sheet 400 has a hollow rectangularshape. As shown in the drawing, the film capacitor sheet 400 is fixed tothe reverse side of the element substrate 101 with an adhesive or thelike.

[0046] According to the foregoing mounting method, the film capacitorsheet 400 also functions as a light-blocking film for preventing thescanning-line drive circuits 130 and 160 from being irradiated withlight by a backlight unit. Also, the film capacitor sheet 400 isdesigned to cover not only the rectangular regions 130 a and 160 a, inwhich the circuits are formed, but also the entire region other than thedisplay region 101 a. Thus, the film capacitor sheet 400 can function asa so-called “partition”, which prevents light from being seen in aportion other than the display region 101 a.

[0047] The interior of the film capacitor sheet 400 is divided into aplurality of film capacitors 410, 420, 430, and 440. The film capacitors410 and 420 are L-shaped, and the film capacitors 430 and 440 arerectangular. Lead wires 412, 422, 432, 433, 442, and 443 protrudeexternally from the film capacitors. These lead wires are bent towardthe surface of the element substrate 101 (FIG. 2(a)) and are connectedto corresponding terminals in the terminal region 107. Accordingly, thecorresponding lead wires are connected to circuits of parts in theintegrated circuit 170 through the patterns on the element substrate101.

[0048] With reference to FIG. 3(b), the structure of the film capacitor410 will now be described. In the drawing, numerals 414, . . . , 414denote five flexible conductor plates, which have protrusions. Betweenthese five conductor plates, four dielectric films 416, . . . , 416 areheld one by one. The protrusions of the conductor plates 414, . . . ,414 are the lead wires 412. The positions at which the lead wires 412are formed are slightly shifted in the horizontal direction.Accordingly, when the film capacitor sheet 400 is formed by stacking theconductor plates 414, . . . , 414 and the dielectric films 416, . . . ,416, as shown in FIG. 3(a), the lead wires 412 protrude as separate leadwires from the film capacitor sheet 400.

[0049] The film capacitor 410 is equivalent to a circuit having fourcapacitors connected in series. The lead wires 412 are provided at bothends of the series circuit and at positions at which the capacitors areconnected. With this arrangement, four capacitors can be formed, andhence effective use of the surface area of the conductor plates 414, . .. , 414 can be made. The film capacitor 420 is arranged similarly to thefilm capacitor 410.

[0050] With reference to FIG. 3(c), the structure of the film capacitor430 will now be described. In the drawing, numerals 434, . . . , 434denote five conductor plates with protrusions. Between these fiveconductor plates, four dielectric films 436, . . . , 436 are held one byone as dielectric. Of the conductor plates 434, . . . , 434, protrusions433 a, 433 b, and 433 c of the first, third, and fifth conductor platesfrom the top protrude at a common position. These protrusions areconnected to form the lead wire 433. Similarly, of the conductor plates434, . . . , 434, protrusions 432 a and 432 b of the second and fourthconductor plates from the top protrude at a common position. Theseprotrusions are connected to form the lead wire 432.

[0051] Accordingly, as shown in FIG. 3(a), the two lead wires 432 and433 protrude from the film capacitor 430. The film capacitor 430 is acapacitor having a multi-layer structure. The potential of the filmcapacitor 430 can be independent of the other capacitors. Thus, the filmcapacitor 430 can be used as a pumping capacitor for use in acharge-pumping boosting circuit (Power supply circuit, etc.).

[0052] After the film capacitors 410, 420, 430, and 440 of types shownin FIGS. 3(b) and (c) are formed in accordance with the purpose anddesired capacitance, all of the film capacitors 410, 420, 430, and 440excluding the lead wire portions are covered with a common film, therebyforming the film capacitor sheet 400. The number of conductor plates414, . . . , 414 and the number of dielectric films 416, . . . , 416deposited in one region, the surface area of these conductor plates 414,. . . , 414, the surface area of these dielectric films 416, . . . ,416, the type of dielectric film, and the thickness of the dielectricfilm are determined in accordance with a desired capacitance and adesired breakdown voltage of each film capacitor.

[0053] An example of a method for forming the dielectric films 436, . .. , 436 will now be described. A known barium titanate workpiece isfired, and the fired workpiece is ground to powder. The powder is mixedwith a binder of a polymeric material such as polyethylene or resist.The mixture is formed into a thin sheet with a thickness ofapproximately tens of μm, thereby producing the dielectric film 436. Inview of the structure of a capacitor, the dielectric coefficient of anormal film capacitor is too low. Because ceramics such as bariumtitanate used in the ceramic capacitor are too hard, it is difficult tomount the ceramic capacitor directly onto the liquid crystal panel.

[0054] In contrast, according to the film capacitor sheet 400 of thisembodiment, barium titanate powder is mixed with a flexible material;the mixture is formed into a film; and the film is used as a dielectric.It is thus possible to ensure a high dielectric coefficient. Since thefilm capacitor sheet 400 can be formed into a flexible film, the filmcapacitor sheet 400 can freely adapt to flexure of a portion at whichthe film capacitor sheet 400 is mounted and to deformation such astorsion. Thus, disengagement due to metal fatigue can be prevented.Also, shock resistance is high. Of course, this embodiment is able toapply for the case of using dielectric material other than the bariumtitanate.

[0055] 2. Specific Examples of Electronic Apparatuses

[0056] 2.1 Projector

[0057] A few examples in which the above-described film capacitor sheet400 or the electro-optical device is used in a specific electronicapparatus will now be described.

[0058] A projector 5400, which is a projection display using theelectro-optical device according to the foregoing embodiment as a lightvalve, will now be described.

[0059]FIG. 4(a) is a schematic diagram showing main portions of theprojection display. In the drawing, numeral 5431 denotes a light source;numerals 5442 and 5444 denote dichroic mirrors; numerals 5443, 5448, and5449 denote reflecting mirrors; numeral 5445 denotes an incident lens;numeral 5446 denotes a relay lens; numeral 5447 denotes an outgoinglens; numerals 100R, 100G, and 100B denote liquid crystal opticalmodulators, which are electro-optical devices having the film capacitorsheet 400; numeral 5451 denotes a cross dichroic prism; and numeral 5437denotes a projection lens. The light source 5431 is formed by a lamp5440, which is a metal halide lamp or the like, and a reflector 5441 forreflecting light of the lamp. Of a light beam from the light source5431, the dichroic mirror 5442 for reflecting blue light and green lighttransmits a red light ray and reflects a blue light ray and a greenlight ray. The transmitted red light ray is reflected by the reflectingmirror 5443 and enters the red-light liquid crystal optical modulator100R. Of the colored light rays reflected by the dichroic mirror 5442,the green light ray is reflected by the dichroic mirror 5444 forreflecting green light and enters the green-light liquid crystal opticalmodulator 100G.

[0060] In contrast, the blue light ray is transmitted through the seconddichroic mirror 5444. For the blue light ray, in order to preventoptical loss caused by a long optical path, light leading means formedby a relay lens system including the incident lens 5445, the relay lens5446, and the outgoing lens 5447 is provided. The blue light ray entersthe blue-light liquid crystal optical modulator 100B through the lightleading means. The three colored light rays modulated by the opticalmodulators enter the cross dichroic prism 5451. The prism is formed bybonding four rectangular prisms. The interior is formed by arranging adielectric multi-layer film for reflecting red light and a dielectricmulti-layer film for reflecting blue right in the form of a cross. Bythese dielectric multi-layer films, the three light rays are combined toform light representing a color image. The synthetic light is projectedby the projection lens 5437, which is a projection optical system, ontoa screen 5452. As a result, the image is enlarged and displayed. Also,the film capacitor sheet 400 is more efficient to shut out a stronglight inside the projection display. Moreover, the film capacitor sheet400 which locates near the substrate has good performance for thepurpuse of backup of the power source.

[0061] 2.2 Mobile Computer

[0062] An example in which the above-described film capacitor sheet 400and the electro-optical device are applied to a mobile personal computerwill now be described. FIG. 4(b) is an elevation view showing thestructure of a personal computer. In the drawing, a mobile computer 5200includes a main unit 5204 with a keyboard 5202 and a display unit 5206.The display unit 5206 is formed by adding a backlight unit at the backof the foregoing electro-optical device 100. On the reverse side of thebacklight unit, the film capacitor sheet 400 is attached. By using thefilm capacitor sheet 400, it will be able to make the mobile personalcomputer to have more thin structure.

[0063] 2.3 Cellular Phone

[0064] An example in which the above-described electro-optical device isapplied to a cellular phone is described. FIG. 4(c) is a perspectiveview showing the structure of the cellular phone. In the drawing, acellular phone 5300 includes a plurality of operation buttons 5302, amouthpiece 5304, an earpiece 5306, and the electro-optical device 100. Abacklight unit is provided at the back of the electro-optical device100. On the reverse side of the backlight unit, the film capacitor sheet400 is attached. By using the film capacitor sheet 400 which has highshock resistance, the cellular phone can also have high shockresistance.

[0065] 2.4 Others

[0066] Examples of electronic apparatuses, in addition to theabove-described electronic apparatuses, include a liquid crystaltelevision, a viewfinder videocassette recorder, a monitor-direct-viewvideocassette recorder, a car navigation apparatus, a pager, anelectronic notebook, a calculator, a word processor, a workstation, avideo phone, a POS terminal, and an apparatus provided with a touchpanel. Needless to say, the foregoing electro-optical device or the filmcapacitor sheet 400 is applicable to these various electronicapparatuses.

[0067] 3. Modifications

[0068] The present invention is not limited to the foregoing embodiment.For example, various modifications can be made as below.

[0069] (1) In the foregoing embodiment, an example of an electro-opticaldevice in which the present invention is applied to a subfield drivingliquid crystal panel has been described. However, the present inventionis applicable to other passive liquid crystal panels. Further, thepresent invention is applicable to all other electro-optical devices.

[0070] Examples of electro-optical devices include anelectro-luminescence device and a plasma display.

[0071] (2) In the foregoing embodiment, an example in which the filmcapacitor sheet 400 is fixed to the reverse side of the elementsubstrate 101 has been described. Instead of this (or in addition tothis), the film capacitor sheet 400 can be fixed to other portions ofthe electro-optical device. For example, as shown in FIG. 5(a), the filmcapacitor sheet 400 can be arranged in the form of a rectangle having awidth equivalent to that of the flexible tape wire 180, and this filmcapacitor film 400 can be attached to the flexible tape wire 180.Because the film capacitor sheet 400 is flexible, the film capacitorsheet 400 can adapt to the flexure of the flexible tape wire 180.

[0072] In FIG. 5(a), the film capacitor sheet 400 is attached to theflexible tape wire 180. Subsequently, lead wires 452, . . . , 452 arebent toward the reverse side of the flexible tape wire 180. On thereverse side of the flexible tape wire 180, a pattern is partiallyexposed. The lead wires 452, . . . , 452 are bonded to the exposedpattern. Alternatively, the film capacitor sheet 400 may be formed to beintegrated with the flexible tape wire 180. As shown in FIG. 5(b), thefilm capacitor sheet 400 can be mounted on a hard wiring board (PWB) orflexible substrate (FPC) 190. Although not shown in the drawing, whenthe hard wiring board (PWB) or the flexible substrate (FPC) 190 is amulti-layer substrate, the film capacitor sheet 400 can be included asone layer in the multi-layer substrate.

[0073] (3) The film capacitor sheet 400 in the foregoing embodiment canbe embedded in a composite build-up substrate. The composite build-upsubstrate is manufactured by a method of stacking new layers, which arereferred to as build-up layers, above and below a core layer(multi-layer substrate to be a core) of a printed wiring board. Themulti-layer build-up substrate is frequently used in cellular phones andpersonal digital assistants. The film capacitor sheet 400 can be appliedto one build-up layer.

[0074] (4) In the foregoing embodiment, when the backlight unit isprovided at the back of the element substrate 101, the film capacitorsheet 400 can be attached to the reverse side of the backlight unit. Thebacklight unit is manufactured in the form of a rectangle havingdimensions equivalent to, for example, those of the display region 101a. The backlight unit, which is provided on the reverse side of theelement substrate 101, is fixed so as to cover the display region 101 a.Since the reverse side of the backlight unit has a relatively large areaequivalent to that of the display region 101 a, the total capacitancerealized by the film capacitor sheet 400 can be increased.

[0075] As described above, according to the present invention, one or aplurality of capacitors is provided in a capacitor sheet which is aflexible sheet. Accordingly, the capacitor can be mounted stably despiteflexure of an electro-optical device or shock applied to theelectro-optical device. In the structure in which the capacitor sheet ismounted in the periphery of a display region or a drive circuit regionis shielded from irradiation light, a light-blocking effect in anon-display region of the electro-optical device can be enhanced.

What is claimed is:
 1. A capacitor sheet forming a capacitor which has asingle-layer or a multi-layer structure, the capacitor comprising: adielectric layer which is a flexible sheet formed by mixing dielectricmaterial powder with a polymeric material; and conductor layers whichare flexible and which are formed so as to hold the dielectric layertherebetween.
 2. An electro-optical device with a capacitor, comprising:the electro-optical device comprising: a plurality of scanning lines; aplurality of data lines; and pixels which are arranged in correspondencewith intersections of the data lines and the scanning lines; and acapacitor sheet as set forth in claim 1, which is fixed to theelectro-optical device.
 3. An electro-optical device with a capacitoraccording to claim 2, wherein the electro-optical device has a displayregion for displaying information by being irradiated with externalirradiation light, and the capacitor sheet is mounted along theperiphery of the display region, whereby a portion in which thecapacitor sheet is mounted is shielded from the irradiation light.
 4. Anelectro-optical device with a capacitor according to claim 2, whereinthe capacitor sheet has shock resistance.
 5. A capacitor sheet accordingto claim 1, wherein the capacitor sheet is formed by a plurality ofcapacitors formed in each region on a surface of the sheet.
 6. Aflexible substrate comprising a capacitor sheet as set forth in claim 1,the capacitor sheet being mounted on a top surface of the flexiblesubstrate or being included as a layer in the flexible substrate.
 7. Acomposite build-up substrate comprising a capacitor sheet as set forthin claim 1, the capacitor sheet being mounted on a top surface of thecomposite build-up substrate or being included as a layer in thecomposite build-up substrate.
 8. An electronic apparatus comprising acapacitor sheet as set forth in claim 1.